Improved impedance source inverter for hybrid/electric vehicle application with continuous conduction operation

This paper proposes an improved impedance (Z) source inverter topology. Compared to the traditional impedance-source inverter, it can reduce Z-source inverter device voltage stress significantly to perform the same voltage boost, and provides the controllable and stable output power in all load condition. The control strategy of the proposed Z-source inverter is exactly the same as the traditional one. An input filter is also proposed to suppress the power source stress due to pulse input current. The operation principle of the improved topology is analyzed in detail. Experimental results are given to demonstrate the new features of improved topology. Compared to conventional topology 32% reduction of dc-link voltage stress and 75% of input current ripple reduction is achieved.